Method and apparatus for stereoscopic X-ray production



METHOD AND APPARATUS FOR STEREOSCOPIC X-RAY PRODUCTION Filed Oct. 15, 1949 S. W. ATWELL July 5, 1955 4 Sheets-Sheet 1 flermzz Wiwei Tram/me! S. W. ATWELL July 5, 1955 METHOD AND APPARATUS FOR STEREOSCOPIC X-RAY PRODUCTION Filed OCb. 15, 1949 4 Sheets-Sheet 5 f fi 5 i W i 1 W IMP k v z I I l/ lll w W 1/4 I CHI/F 7 y I MET-15:11:... 1|. l\ N I N VEN TOR. fliz'ermzz fiffllzmeil,

S. W. ATWELL July 5, 1955 METHOD AND APPARATUS FOR STEREOSCOPIC X-RAY PRODUCTION 4 Sheets-Sheet 4 f Filed Oct. 15 1949 grwe/vvm fiermzz Wfwel ATTOR N EY United States Patent 0 METHOD AND APPARATUS FOR STEREOSCOPIC -RAY PRODUCTION Sherman W. Atweli, Brookline Village, Mass. Application October 15, 1949, Serial No. 121,534 23 Claims. (Cl. 250-60) This invention relates to the art of radiography, and in its preferred adaptation it is particularly applicable to stereoscopic roentgenography including within its scope combinative features of focal-film coordination and observation.

Medicine has used the X-ray to wide advantage. However roentgenographic examination has been essentially limited to a gross superficial study comparable to the superficial examination aliorded the gross pathological specimen. The X-ray image is created by the aggregate shadows of the many individual living cells of the body. Diagnostic roentgenological interpretation is the art of recognizing abnormal anatomical architecture in the shadows cast by the large selective cell-clusters which are the muscles, bones, vascularities, etc.

Thus every X-ray image includes minute detail which is not discernible through available apparatus or technique and therefore is of latent significance in view of the possibility that such details may be of primary value in any given diagnosis. The resort to microscopic exami nation per se has proved to be of little if any value, tending to result in a confused effect as distinguished from a clarification oi the minute details under scrutiny, and particularly since to be of any value a plane separation in the image is necessary, such as that afiorded in stereos- PY- However, the reliance upon magnification in connection with binocular third-dimensional scrutiny of X--ray images requires, among other details, a substantially perfect matching of relatively small areas of the object, as revealed by two stereoscopic films. To attain such matching, it is necessary to eliect simultaneous X-ray exposure of two films by two separated X-ray tubes, respectively coordinated with said films. Within the purview of the invention, such simultaneous exposure of the films, correlated for stereoscopic observation of the object, is provided through the apparatus and technique of the present invention which is adapted for observation of the stereoscopic-aily related films under conditions of magnification. Thus even as the invention of the microscope has been closely related to the basic medical science of histopathology, so can precise magnification of the X-ray image, within the purview of the present invention, under roper conditions, offer vast potentialities to the study of living tissue in situ.

it is known that any extended magnification of a single conventional roentgenogram will result in a confused superimposition of all the facing structure's involved. While this objectionable situation would seemingly require an effective separation of planes, no expedient manner of accomplishing this result has been attainable heretofore in the prior art. The procedure known as lsminography for recording a selected plane of the body does not fulfill the requirements for magnification because of the limitation of depth and the long exposure which introduces an element of involuntary motion with an attendant adverse effect on the fine detail of the image. Conventional roentgenographic stereoscopy does distinguish sepaice rate planes, but when exposures for third dimensional examination are made in sequence, the involuntary body motion occurring in the interval between exposures would not permit stereoscopic matching of small magnified areas. Furthermore, even if such an examination were to be made on an inanimate or well-mobilized area, the study of such films through any conventional stereoscope equipped Wlil'l positive lenses or concave mirrors might afford the necessary concentration on the dimensions of width and height, but could not exercise the necessary selective limitation over the dimension of depth. It must also be noted that stereoscopic films taken by conventional methods would have the depth effect so reduced by magnification that the results Would be nearly two-di- U mensional.

Attempts have been made in the prior art to obtain simultaneous exposures for stereoscopically correlated images. However, these efiorts were based upon tubefihn relationships which must result in distortions, and when viewed without correction in a conventional stereoscope must result in an aberrant image.

Thus the prior art is utterly without contemplation of the significance or advantages obtainable through stereoscopic magnification and its correlation with exaggerated image depth, pursuant to the present invention.

it is an object of the invention to obviate such ditficulties and uncertainties as hereinabove described in connection with stereoscopic roentgeriography of the prior art.

Another object is to provide an improved radiographic technique aliording optimum image detail and undistorted image relationships for stereoscopic observation.

An additional object is an enhanced coordination of stereoscopic images obtained under conditions of exposure which minimize the effects of involuntary object motion.

An important object is to obtain stereoscopically related X-ray films by simultaneous exposure of two roentgenograms through two respectively coordinated and separated X-ray tubes under conditions which adapt the said films for microscopic or magnified observation of the minute detail prevailing at any given matched area of the subject of scrutiny.

An added object is to devise an improved technique applicable to stereoroentgenography for simultaneously attaining related stereoscopic films of exaggerated optimum depth substantially free from the distortions of involuntary motion of the object, which provide as a result of magnification a stereoscopic image of improved detail.

A further object is an improved roentgenographic apparatus alfording coordinated film exposures which are particularly adapted for magnified stereoscopic observation.

A material object of the invention is an enhanced stereoscopic X-ray apparatus adapted for the simultaneous exposure of two stereoscopically related films by two respectively coordinated and separated X-ray tubes under conditions rendering the films susceptible to magnified observation.

A further important object is an integral stereoscopic X-ray apparatus combination permitting the simultaneous exposure of two stereoscopically related films by two respectively coordinated and separated X-ray tubes under such conditions that the said images are susceptible to scrutiny by magnified observation, the said apparatus involving a flexible support of the matched films permitting their synchronous movement for depth considerations of the given areas and their simultaneous adjustment for submitting any portion of the image to stereoscopic observation, the said integral combination including a stereoscopic magnifying viewer.

A significant object is a stereoscopic X-ray apparatus correlated with a magnifying stereoscope providing coordinated images of optimum depth, effective magnification, and generally enhanced detail.

Still another object is a stereoscope adapted to coordinate the dimensions of width, height and exaggerated optimum depth by appropriate magnification, whereby the depth is proportionately correlated with the image width and height to provide a magnified image under conditions of third dimensional or stereoscopic observation.

Other objects, advantages and features of the invention will become apparent from the following description read in connection with the accompanying drawings in which similar elements are designated by like numerals.

Fig. l is a diagrammatic plan view of an X-ray apparatus, showing the correlation of tubes, obicct and films, together with control means adapted for affording simultaneous coordinated exposure of the films.

Fig. 2 comprises an clevational showing of the combination of Fig. l, exclusive of the control means.

Fig. 3 relates to a fragmentary vertical section taken along line 3-3 of Fig. l, and is directed to an expedient film retaining device or cassette together with a head rest attachment shown in elevation.

Fig. 4 indicates a fragmentary detail viewed along line 4--4 of Fig. 2, including the junction between the cassette supporting frames.

Fig. 5 pertains to a supporting structure for the film retaining assembly, and adapted for providing correlated observation of related areas of stereoscopically associated films.

Fig. 6 is a plan view of the apparatus shown in Fig. 5.

Fig. 6a is a diagrammatic plan view of an alternative optical system for the stereoscopic observation housing shown in Fig. 6.

Fig. 7 represents an end view of the structure indicated in Fig. 5 including the stereoscopic viewing attachment.

Fig. 8 is a horizontal section on the line 8-8 of Fig. 5.

Fig. 9 is a vertical section taken along line 9-9 of Fig. 5.

Fig. 10 is a vertical section of a device attached to the respective frames supporting the stereoscopically exposed films, and permitting a relatively fine vertical ad justment of each frame with respect to the other.

Fig. 11 is a fragmentary perspective view of an upper corner of a film holding frame.

Fig. 12 provides a diagrammatic indication of the exposure in accordance with the invention, of the stereoscopically related films by two separate X-ray tubes, each correlated with one film, illustrating the simultaneous exposure of the films and the relative indication concerning image details at different depths of object shown in cross section at a predetermined. area.

Fig. 13 pertains to a diagrammatic illustration showing the correlation of the stereoscopically related films with matched areas coinciding to demonstrate detail located at a given depth, said detail having been brought into the area of inspection relative to the magnifying observation device.

Fig. 14 represents diagrammatically the adjustment of the relative position of the stereoscopic films shown in Fig. 11 to bring other matched areas located at a different object depth into the area or zone of stereoscopic observation under the same conditions of magnification.

Referring more particularly to the features of the invention as illustrated by the various figures of the drawings, which are representative of desirable embodiments and not intended to be restrictive of the scope of the invention, the combination indicated in Fig. 1 provides an expedient apparatus for simultaneously exposing two films for subsequent magnified stereoscopic observation. Thus the combination comprises radiopaque tunnels 1 and 2 diverging toward and ultimately merging with the peripheral housing 3 which may be open at the bottom and top. Desirably this housing is likewise of radiopaque character. The end wall of this housing is determined by a frame structure 4 adapted for supporting the film retaining device or cassette 5.

The entire apparatus, including the tunnels, housing and tubes and means for supporting the cassettes is desirably mounted in permanent position and in accordance with any expedient manner. It is desirable that the relative tube-focal plane relationship be precisely maintained in the fixed association, embodying the features of the in vention as described hereinbelow.

The respective tunnels 1 and 2 converge toward their ends remote from housing 3 and are desirably of similar length. X-ray tubes 6 and 7 are positioned at the said converged tunnel ends and the hypothetical line between the targets of these tubes is preferably horizontal. In view of the equivalent lengths of the respective tunnels l and 2, the tubes 6 and 7 are substantially equidistant from any object 10 centrally positioned within housing 3. it will be understood that tubes 6 and 7 embody so-called targets pursuant to conventional structure, and for purposes of description herein, these targets are considered to be point sources of radiation.

The tunnels 1 and 2 may manifest a generally pyramidal or conical configuration with the X-ray tubes located adjacent the smaller ends, while the enlarged ends of the tunnels are correlated with the adjacent housing 3 wherein the object 10, such as a person to be X-rayed, is positioned. Preferably the respective axes or center lines 8 and 9 of the tunnels intersect in the object at an angle of approximately 90. Thus the X-rays emanating fromrespective tubes 6 and 7 in effect assume a relationship corresponding with axes lines 8 and 9 and the attendant angular relationship of approximately 90.

The object 10 is desirably positioned in zone 11 which essentially embraces the area adjacent housing 3 at which the X-rays from tubes 6 and 7 intersect in a substantially right angular relationship. Gate or door 12 is shown at H the confluence of walls 13 and 14 of respective tunnels,

' l and 2 to permit ingress and egress of the object to the said zone 11. This gate may expediently comprise panel 15, hingedly attached to side 13 at 16, and panel 17 hingedly attached to side 14 at 18. In the normal position of panels 15 and 17, they serve to complete the lateral closure of zone 11, with their edges 18 and 19 meeting along the line 20. Similarly to the aforesaid tunnels, gates 15 and 17 may desirably be of radiopaque mate rial. Accordingly the tunnels 1 and 2 with their attendant panels 15 and 17 in closed position comprise sym metrical conduits adapted for retaining the X-rays emanating from the respective tubes 6 and 7 and directed through the object 10 to films 21 and 22, which are to be ex-:

posed.

It will, however, be understood that the aforesaid provision of panels 15 and 17 for gate 12 is not a requisite of the apparatus structure, since the omission of such panels, resulting in an access opening 12, will similarly function in suitable manner.

In order to facilitate the simultaneous exposure ot filrns 2'1, 22, it is advisable to utilize any effective means for absorbing secondary radiations, and thereby regulating the flow of X-rays in the predetermined direction defined by the respective tunnels 1 and 2. Thus Bucky grids- 23 are desirably positioned within housing 3 in a manner a to effectively extend the outer sides or walls 24 and 25 respectively of tunnels 1 and 2. These diaphragms are shown affixed at one end to the respective walls 24, 25

which they extend. At their other end they may be at-.

tached to the frame structure 4 on opposing sides of rod .26, at the end. of which head rest 27 and body-contact: memb r 23 may be provided, as indicated in Fig. 1, the

rasse said body contact member being desirably radiolucent affixed at its extremities to the walls of housing 3. Thus body contact member 28 may further function to define zone 11 wherein the object is positioned.

As shown in Figs. 3 and 4, the film retaining device 5 may effectively consist of a conventional cassette within which the unexposed X-ray film is contained. The said cassette assembly 5 is of a dimension adapted to seat within slots 30 of the aforesaid frame structure 4.

Afiixed to the rear of frame structure 4, there is pro vided ear element 31 functioning as the support of the aforesaid rod 26. Expediently the said rod may comprise a vertically extending portion 32 and a relatively horizontal portion 33, the latter assuming any predetermined configuration and direction adapted to maintain the lean-to device, such as the head rest 27 and body contact member 28 integral therewith, in appropriate position for the object. The said portion 32 of the rod may extend through an opening in ear 31, wherein it is desirably in permanent attachment, with the head rest 27 retained at a predetermined elevation by set screw 34.

For the purpose of simultaneously exposing films 21 and 22, tubes 6 and 7 may be discharged by control means such as diagrammatically indicated in Fig. 1. This con trol means may include transformer 35 applicable to tube 6 and transformer 36 effective for regulating the voltage for tube 7. The said transformers 35 and 36 are shown connected to a single timer device 37, and accordingly the current passing through the timer will simultaneously function through the respective transformers 35 and 36 to activate tubes 6 and 7. It will be understood however that the X-ray apparatus may be operated without resort to simultaneous exposure of the respective films, this being accomplished merely by relying on individual control circuits for the respective tubes 6 and 7.

A desirable embodiment of stereoscope supporting structure for the film retaining assembly and its attendant frame structure, as well as the stereoscopic observation means is the apparatus primarily indicated in Figs. 5, 6 and 7. lhe standards 41 are shown integral with flange 42, the latter being adapted to maintain the structure under suitable conditions of equilibrium and is desirably fixed to a table or other suitable base 42'. Mounted on the said standards 51 is the frame assembly 43, comprising vertical guides 44 together with top and bottom horizontal members 45' integrally attached to the said members 44 at their respective ends as shown in the drawing. Reinforcing braces 33 are affixed at their respective ends to vertical guides 44 in order to afford added stability to the supporting structure.

An additional frame structure 46 is adapted for supporting an assembly 49 of plates between which the exposed films are sandwiched. This plate assembly is shown in Fig. 9, where respective plates thereof 47 manifest characteristics of transparency. The exposed film in this assembly adapted for observation is designated as 48.

Referring to Fig. 9, it will be seen that the film assembly 49, comprising plates 47 and film 48, is seated in grooves or channels 5%, 51 of frame structure 46, and as indicated in Fig. 5, two such frame structures 46 and 46 are mounted for observation of the stereoscopically related films sandwiched between the respective transparent plate assemblies.

In order to render the aforesaid frame structures 46 and 46' movable as an assembly as well as relative to each other for effecting their separation or approximation desired, they are retained in slots or channels 53 of carriage 52, which is in turn flexibly mounted for movement on the frame assembly 43 supported by standards 41, as previously described. An expedient coordination of the said film assembly frames 46, 46' is shown in Fig. 5, wherein a screw threaded element 54 having reversely threaded portions is movable in lugs 56 and 57 respectively secured to frames 46, 46. A knurled member 58 is secured to the threaded element midway of its ends to channels 53 within which operate the same and move the frames 46, 46' toward or away from each other. The said threaded lugs 56 and 57 are desirably swiveled in order to afford an element of play to permit slight vertical or tiltable adjustment of frame members 46, 46 as further described hereinbelow.

Concerning the supporting means or carriage 52, it includes horizontal members 59, 6t) which at their extremities are attached to vertical members 61. The said members 59, 64) are provided with the aforesaid grooves or frames 46, 46 are attached for lateral movement as previously indicated. Attached to vertical members 61, there are provided guide rollers 64 which ride in channels or grooves 63 provided in the vertical guide members 44 of the frame structure 451. Affixed z to the upper horizontal member 59 of film assembly carcross member 45 thereof.

the vertical positioning of the exposed films porting means for the exposed films,

riage 52 are cables 65 which appropriately ride on pulleys 66 that are supported by brackets 6'7 which may in turn be fixedly attached to the upper portion of supporting frame structure 33, such as to the upper horizontal or The free end of cable 65 is desirably provided with an appropriate counter weight 68 adapted to maintain the carriage 52 in a given position, at the same time permitting expedient movement of the said carriage through the manifestation of a pulling effect 011 cable 65. Thus the film assembly carriage 52 may be subject to displacement up and down supporting structure 43, thereby affording a similar movement to the exposed films retained by their assemblies 49 in frames 46, 46'. This movement enables a flexible variation in along their vertical axes relative to the line of observation afforded by the stereoscope.

For maintaining an appropriate correlation of the viewing or observation device with the above described supthe stereoscope housing may desirably be mounted in unitary association with the film supporting structure 43. This is illustrated in Fig. 7 wherein standards 76 shown integral with stereoscope housing 75, ride at their lower portions 77 in a groove or channel 78 through the coordination provided by the said groove or channel with bar members '79. The said bar members may be attached to the lower cross or horizontal members 45 of supporting structure 43.

in order to effectuate the movement of stereoscope housing 75 on bar members '79, rack means 233 on the said bars are coordinated with pinions 31 on the lower portion 77 of standard 76, preferably through any handle or knurled element 82 operatively integral with said pinions 81. Thus the stereoscope housing 75 may be laterally adjusted relative to film frames 46, 46' through the functioning of the rack and pinion mounting indicated.

The viewing device diagrammatically illustrated in Fig. 6, and comprising the details within the housing '75, involves reflecting mirrors 33, a4 coordinated with any expedient optical system of magnifying lenses 85, 86, the latter being correlated with additional reflecting mirrors 87, 88. It will be understood that the association of the said mirrors and lenses is adapted for adjustment, pursuant to usual practice, for satisfying the particular requirements of any observer, such as the preferred interpupillary details characteristic of that observer. Alternative to the adaptation of magnifying lenses, mirrors 87' and 88' may afford requisite magnification by their appropriate concavity, as shown in Fig. 6a.

It will be understood that the housing 75 which comprises the magnifying optical system may be subject to variations in its power pursuant to the discretion of the operator as well as the dictates of pertinent circumstances, said changes of power being possible due to the focusing properties attained by rack and pinion its), 81. It will be seen that the larger field afiorded by a relatively low power of magnification will permit a broad area of inspection, while concentration upon the smaller details in the image is possible with greater magnification. This permits a broad field examination without denying the advantages of 7 smaller-field, higher-power visualization of questionable areas.

Light sources 89, 90 are positioned in appropriate relationship to the rear of the exposed film assembly retained by frames 46, 46, and opposite mirrors 87, 88. These light sources may be supported in predetermined manner, as by attachment in any expedient way to supporting structure 43 of the standards 89 and 90, which may, if desired, be longitudinally adjustable, or the said light standards may be based on table 42 as shown. The position of the observer is diagrammatically indicated at 69, which may be taken as designating the eye pieces of the viewing apparatus. As shown in the drawings, the position of housing 75, particularly the aforesaid mirrors and lenses therein, is desirably situated so that the vertical and horizontal axes of both housing 75 and supporting structure 43 are substantially aligned.

The dimension of depth in the stereoroentgenogram is controlled by the intertube separation. By way of illustration, with the two central rays intersecting the object at 90, the image depth will have been exaggerated to the point where it could not be successfully viewed in any conventional stereoscope.

In any stereoscopic image the addition of magnification will reduce the depth dimension. To suthciently correct the aforesaid gross exaggerated depth to the point that would permit examination, a magnification of approximately times has been found satisfactory, although it will be understood that the extent of this correcting magnification may be subject to variation depending upon the optical characteristics and stereopsis ability of the individual viewer. Further magnification toward the limits of tolerance of the resolving power of the emulsions used will increase the ease of third-dimensional viewing, bringing into view delicate masses of detail which otherwise cannot be observed with the unassisted eye by the usual third dimensional or stereoscopic observation.

With magnification the field of view in relation to the dimensions of width and height is considerably narrowed. Although this field is narrowed, matched areas comprising the diminished portion of the image can be seen as a limited zone of observation when in line with the optical axes.

Thus with the film assemblies capable of being adjusted relative to each other and of being moved together, that t is, as an assembly, either vertically and/or in a' transverse direction, any and all portions of the two films retained by the assemblies can be brought to a position before the viewing system.

As shown in Fig. 5, the knurled member 58 is positioned between frames 46 and 46, and since threaded element 54 with its reversely threaded portions 55, 55' is coordinated with lugs 56, 57, rotation of knurled wheel 58 in one direction will function to draw frames 46 and 46' toward each other, while actuation of the knurled wheel in the opposite direction will provide a reversed movement of frames to, 46, that is, away from each other. It will be seen that the extent of lateral movement of the frames 46, 46' is dependent upon the details of the reversely threaded screw member 54 as well as the dimensions of carriage 52 for the said frames.

It is through the expedient of the said reversely threaded screw member 54 that the requisite or predetermined depth selection relating to the matched areas of the image is attained. Thus with a given zone of the object located at a predetermined depth thereof, subject to scrutiny through magnified stereoscopic observa tion by the correlation or alignment of said zone with the line of binocular observation, a different depth of the object may be brought into visual focus under magnification, through operation of knurled wheel 58, by laterally displacing the frame members 46, 46 either-to horizontally separate the frames relative to each other or to.

effect their movement toward each other-that is, approximating them with respect to each other. Accord ingly selection in the depth of image subject to scrutiny may be attained through the appropriate manipulation of the said knurled wheel 58.

Desirably, an additional adjustment should be available for bringing the detail of the stereoscopically related films into critical coincidence. Thus with given matched areas at a predetermined depth in position for scrutiny with respect to the plane of binocular observation, furthcr adjustment may be necessary due to a discrepancy attributable to the initial positioning of the exposed films in their respective assemblies 47. Due to such a discrepancy, precisely the same image areas on the respective films may not match and the requisite critical fusion or adjustment may be attained by a device illustrated in Figs. 5 and 10. This device comprises a nut 91 attachedto the vertical portion of frame member 46. Thus the said nut 91 is internally threaded for coordinated reception of thumb screw 92, which extends through the said nut and terminates in shouldered end portion 93 of a lesser diameter than the threaded portion of the thumb screw. The said portion 93 may be free from surface threads and is adapted to seat within a coordinated opening in the body of shoe 94 on which roller 95 is mounted. The said roller is adapted to ride in groove 53 of carriage 52. Portion 93 of thumb screw 92 may also be provided with a superficial annular groove 96 into which the end of set screw 97 may project in frictional engagement for locking shoe 94 in position. The opposite side of frame member 46 may be likewise supplied with a similar adjustment-means as shown in the drawing. Thus by adjustment'of thumb screws 92, the frame member 46 may be tilted upwardly or downwardly as desired. As shown in Fig. 5, precisely the same means of adjustment is provided with respect to frame 46'.

The attaining of angular variations in the position of the stereoscope for viewing may be accomplished through the details of attachment of supporting structure 43 to standard 41. As shown in Fig. 7, the upper portions of standards 41 are angularly disposed with respect to the principal vertically extending portions 71. Integral with the portions 70, there may be a plate member 72 which is atfixed to the rear of vertically extending guide members 44 of supporting structure 43. The portions 70" of said standards 41 are provided with a universal joint 73 which is susceptible to being locked through the expedient of set screw 74. Thus the end part of portion 70 of standard 41 may be angularly varied as to its position,

with the result-that theentire supporting structure 43,

together with the frames and elements mounted thereon may be angularly disposed in any predetermined manner through the functioning of the said universal joint 73.

The attendant flexibility of this portion of the apparatus may accordingly be summarized as affording an angular variation of the supporting structure 43, whereby- 1 the-carriage 52 and film frames 46, 46' are likewise simultaneously afforded angular variation through anypredetermined extent.

Thus the over-all coordination of the stereoscopic ments for the variable positioning of the images and their relative adjustment; as well as the integral stereoscopic viewing device. 1

1 Moreover it should be noted that in the exposing apparatus a linev drawn between the two tube targets, which may be considered to be point sources of radiation, isv

substantially parallel with the transverse axis of the focal plane common to the two films, and therefore with respect to the transverse axis of the films per se, when they are mounted in their respective film holders for exposure. Thus when the focal planei's in vertical position, the b.ori-' z ontal plane containing the said hypothetical line between the two tube targets will be substantially perpendicular to the said focal plane. in othr Words, a horizontal line perpendicular to the intertarget line will be substantially at right angles to the focal plane.

After the roentgenograrns 'e been processed and placed in the stereosc L observation, the transverse axis of their common focal plane is in turn substantially parallel with a line drawn between the center of the two eye pieces. This may be described to the effect that the optical axis of the viewing eye pieces is maintained in substantially parallel relationship with the transverse axis of the films in their common focal plane, and a line perpendicular to the optical axis will likewise be at right angles to the focal plane or" the processed films.

Moreover it may be assumed that the two films comprise a common focal plane, whether in the unprocessed state, mounted for exposure or in the processed state mounted for observation. Thus it may be said that the intertarget line of the X-ray tubes and the optical axis of the stereoscope are both parallel to the transverse axis of the focal plane.

in addition, the lines of Xrays emanating from the respective tubes, or the paths determined by the said X-ray lines from the tubes, desirably extend substantially at right angles to each other. Accordingly when the said respective lines or paths of X-rays project at substantially right angles to each other through the object, the said lines or paths or" radiation will extend toward the films, positioned for exposure in a common focal plane and correlated with the respective tubes, to contact the said films for exposure at angles of approximately 45 However as previously stated, the aforesaid angular relationship of the X-ray paths is not intended to be restricted to 90, since angulations of other degrees can suitably afford the depth exaggeration which lends itself to proportionate correlation with the other dimensions of the image by magnification for purposes of stereoscopic magnified observation.

in operating the apparatus, assuming that a thoracic diagnosis is contemplated, the patient enters housing 3 through gate 12. The patient is positioned at the zone 11 in proper proximity to the contact member 23 and with his chest aligned between tubes and films.

With the apparatus constructed for simultaneous exposure of films 21 22, as shown in Fig. 1, it is then merely necessary to close the electrical circuit through the timer 37 coordinated with transformers 35 and 36. Upon energizing the said electrical circuit, the tubes 6 and 7 are simultaneously energized, resulting in the emanation f X-rays through the respective tunnels 1 and 2 toward the aforesaid films. Substantially all the rays issuing from tube a are directed through the radiopaque tunnel 1 through the patient it; and thence through grid 23, with the result that film 2.2 is exposed. At the same time the rays from tube 7 through radiopaque tunnel 2, thence through the object and finally issuing from grid 23 for exposure of film 23. However, the radiation from tube 6 has been so contained 'thin tunnel ll that it does not contribute to the exposure of film 21. Conversely tunnel 2 protects film from the rays of tube '7. Thus the rays from the respective tubes s and 7 impinge on the object and the films at different angles, dependent upon the angular association of the said tunnels 1 and 2.

Upon removing the exposed films 21 and 22 from the X-ray apparatus and after suitable processing, they are appropriately mounted for stereoscopic observation. Thus the exposed films may be sandwiched between glass plates, broadly pursuant to the showing in 9. This assembly 49 is desirably seated in the cha nel Ell of frames 46, 46' adapted to facilitate the handling of the films. The said frame structures and so are in turn seated in the carriage 52 as shown in Figs. 5, 6 and 9. in view of the features of construction, the said frame members 46v T6 and 46' are by predetermination coordinated with the light sources 89 and 92"; which together with the stereoscopic housing are mounted in correlated association for a facilitated and resilient observation of the exposed films maintained in position by the said frames 46 and 46.

As described hereinabovc, fro 1e members 46 and 46 are movably supported by carriage and they are correlated with light sources as and 9d at their rear, with stereoscope housing '75 appropriately positioned in front, that is on the side from which the films are to be observed. Moreover the viewing device together with the film supporting means and light source are expediently mounted on the same fundamental base, affording an extremely resilient apparatus for utilizing the advantages of facilitated observation applicable to the particular film characteristics attainable with the X-ray apparatus. Thus the features of the X-ray apparatus are in effect coordinated with the means for mounting and stereoscopically observing the exposed films obtained with the X-ray apparatus.

The function of the apparatus combination, as well as the technique of the procedure within the purview of the invention, is illustrated by a reference to Figs. l2-l4. It should, however, be understood that there is no intent to be restricted in terms of the said explanation or in any theory applicable to the technique of operation presented. Referring to the object lid in Fig. 12, assumed to be the patient standing in the position with back to the films 21, 22, the sternum or breast bone of the object is designated as 1G5 with the corresponding exposures on films 2-1 and 22 being indicated as 1-36, respectively. The trachea, or Windpipe, 163 provides shadow or image portions 109, Ill on said films 21 and 22 respec lvely. The spine of the object is indicated at 115'. it should be understood that the said sternum 1&5, trachea 1&8, and spine 115 are at different depths of the object viewed the direction of the source of X-rays. For reference purposes, the depth of the sternum within the chest is designated at Z, the depth of the trachea as X, and the depth of the spine as Y." For further facilitating the con eration, the sternum 105, the trachea 368, and the spine 17155 are represented as being positioned or aligned, for purposes of illustration, in the area of inspection 1111. Thus while all three points of the object are within the area of inspection 111, they are obviously at different depths thereof and the position of their corresponding images on films 21, 22 are accordingly at variance relative to each other.

As shown in Figs. 13 and 14, zone M2 indicates the area covered by the viewing device duri g a complete horizontal excursion of frame structures 4-5, as. Zones 113 and 114 indicate similar areas covered during a complete vertical excursion. The areas where these two zones intersect are the areas subject to view in Figs. 13 and 14 and are designated by he and 16. The stereoscopic image resulting from the visual fusion of these two areas is the zone of observation. Because of the approximation of the frame assembly 46 and 46' the head of the sternum as indicated by X-ray shadows M36, Jill? is brought into visual coincidence, that is, the image of the sternal head at depth Z is brought into the area of inspection under conditions which permit examination, as shown in Fig. 13.

By separating films 21, 22 through the manipulation of knurled wheel 58, it will be seen that the shadows 10?, of the trachea the. are brought into the zone of observation 116, file, as shown in Fig. 14, and corresponding with depth X. By further separation of films 21 and 22, the image of spine 115 may likewise be focused within the zone of observation 116, 116' at depth Y. It will be understood that alternatively the films 21, 22 may be moved horizontally to laterally approach or approximate each other by manipulation of the said knurled wheel 58, thereby varying the planar depth in the opposite direction from the effect attained through separating the l in Fig. 12, ll? is do as indicative of an early cancer lying lower in the chest than the cross section here shown, and casting shadows 11% and 119 as shown in Figs. 12 and 13. Starting with the assembly in position as shown in Fig. 13, if the two films as an assembly are synchronously raised and moved to the left and the proper depth adjustment made so that the matched portions 118 and 119 are presented to the eyes through the optical magnifying system, the tumor will be in the field of observation H6, H6. Moreover any long and tortuous anatomical part such as a bronchus or rib in the chest or the convolutions of the intestine in the abdomen may be followed throughout its entire length by proper synchronized manipulation of the three different controls of film-eye relationship: vertical, horizontal and depth.

It will accordingly be seen that pursuant to the tea tures of the present invention, an X-ray apparatus and procedure are afforded for exposing films under novel conditions in a manner to correlate them for enhanced stereoscopic observation, permitting a selection of planes and dilferentiations of nuances and an amplified consideration of the image details not heretofore possible. The fundamental aspects of the invention are based upon the adaptation of an extraordinary tube separation for the exposure of the respective films intended for stereoscopic association, the extent of said separation being such as to afford an unusual element of gross image depth, the dimensions of width and height of the said image bearing a fixed relationship to each other and minimized by the said depth. While the contemplated image within the scope of the invention is such as to be inconsistent with conventional stereoscopy, and therefore unacceptable to unassisted visual capacity, by resort to appropriate magnification of the gross image, the exaggeration is corrected, that is, the depth dimension is proportionately reconciled with the enlarged dimensions of width and height, whereby an improved stereoscopic observation is possible affording details not heretofore attainable.

Thus the details of the image view are magnified and free from distortion, which is contrary to the effect of magnification as applied to conventional stereoscopically related films. in addition an improved clarity of observation is afforded, and by virtue of the flexible attributes of the invention, a comprehensive study of any given areas or portions of the image is rendered possible. Moreover by the simultaneous exposure of the films, the image irregularities attributable to involuntary motion are effectively avoided, whereby the exposed films are in effect perfectly matched both as to their gross aspects or any given details or areas.

In brief and without intending to be restricted to any particular theory or by the explanation herewith, the invention involves the coordination of magnification with the wide divergence or separation of the X-ray tubes for obtaining independent exposures of stereoscopically related films, the magnification permitting the utilization of the aforesaid exaggerated tube separations, and the latter in turn making possible expedient simultaneous exposures of films correlated in complementary position with each of the X-ray tubes. At the same time, the simultaneous exposure of the films affords optimum detail, under magnification, of the stereoscopically related images.

As previously indicated, the details of procedure'and apparatus described hereinabove represent optimum embodiments of the invention, and it will be understood that they are subject to substantial variation, within the scope of the invention. For example although the tube separation providing ray intersection of approximately 90 has been found to be particularly effective in affording stereoscopically related images of enhanced detail under conditions of magnification and essentially free from distortion, this angle may be subject to variation in accordance with the discretion of the skilled operator and in view of the particular conditions which are applicable, such as the characteristics of the apparatus utilized or 12 of the operator. Moreover and notwithstanding the preference of simultaneous exposure of the correlated films, the apparatus may be utilized or the process performed under conditions where each film is subject to independent exposure.

In addition, features of the invention may be attained by utilizing a single X-ray tube in lieu of the preferred arrangement of the apparatus described, this being for example possible through the expedient of shifting the given tube in accordance with the fundamentals disclosed for attaining an exaggerated image depth, subject to ultimate reconciliation with stereoscopic viewing of the exposed images by resort to magnification. However such a procedure ordinarily may not exclude the effects of involuntary movement by a patient, such as heart motion in the chest or peristalsis in the abdomen. Therefore this procedure under normal circumstances while not eflicient in the vital areas of the chest and abdomen would present few problems attributable to motion in the case of the head and extremities. Likewise the variations of the preferred apparatus may include the omission of resort to a single circuit involving a timer and simultaneous exposure of the tubes, it being possible to operate within the latitude of the invention by independently actuating each tube.

Similarly the features of the invention are not restricted in their adaptation to stereoscopic roentgenography. They are generally applicable where there is contemplated any type of radiographic exposures involving a stereoscopic sequence, and with respect to general photographic films taken in stereoscopic relationship.

In summary the invention permits the stereoscopic examination of an objective area under optimum conditions for diagnostically determining by stereoscopic ro- I entgenography a comprehensive visualization of the prevailing conditions applicable to the object, either from the gross image aspects or at any given unit areas of interest, while at the same time eliminating or substantially minimizing the difficulties and uncertainties which have heretofore persisted and thwarted attempts in this connection.

While I have described my invention in accordance with desirable embodiments, it is obvious that many changes may be made in the details of construction,

and in the combination of parts, as well as in the features of procedure, without departing from the spirit of the invention as defined in the following claims.

Having thus set forth my invention, I claim:

1. The method of producing stereoscopically related images which comprises positioning an X-ray film surface in respective complementary relationship with of at least two each respective sources of radiation, said film surfaces and radiation sources being separated to an extent such that the respective paths of the rays emanating from them will intersect and pass through the object at an angle at which the image depth of the resultant film surface exposures will be exaggerated and inconsistent with normal unmagnified stereoscopic observation, exposing the film surface in complementary relationship with each respective source of radiation through the said object, processing said films to develop them, and stereoscopically observing the resultant image under conditions of magnification of an extent adapted to reconcile the exaggerated image depth with the image dimensions of width and height.

2. The method of producing stereoscopically related films which comprises exposing an X-ray film through a predetermined object by a given X-ray source, exposing at least one other stereoscopically related X-ray film through the said object by X-rays emanating from a source spaced apart from the first X-ray source, the said films being positioned in a common focal plane having its transverse axis parallel to a hypothetical line drawn between the targets of the respective X-ray sources, the distance of separation between the respec-- aviaeoe tive X-ray sources being to an extent that the image depth of the exposed films will be exaggerated and inconsistent with the normal capacity for unmagnified stereoscopic observation, exposing the said X-ray films through the object by the said respective sources of X-rays, processing said exposed films to develop them, and stereoscopically viewing the resultant images under conditions of magnification adapted to reconcile the exaggerated image depth with the image dimensions of width and height for observation consonant with normal stereoscopic vision.

3. The method of producing stereoscopically related films which comprises exposing an X-ray film through a predetermined object by a given X-ray source, exposing a second stereoscopically related XTray film through the said object by Y-rays emanating from a source spaced apart from the first said X-ray source, each or said films being equidistant from the said respective X-ray sources by which they are exposed, the distance said X-ray sources are spaced apart being to an extent that the image depth of the exposed films will be exag erated and inconsistent with normal unmagnified visual capacity for stereoscopic observation, processing said exposed films to develop them, and stereoscopically observing the resultant images under magnification of such an extent that the exaggerated image depth is reconciled with the ra fied image dimensions of width and height.

The method of producing stereoscopically related films which comprises positioning two X-ray tubes apart from each other and correlated with a given object, placing an X-ray film in complementary relationship with each tube and adapted for respective exposure through the said object by the X-rays emanating from the tube with which it is complementary, said tubes being substantially equidistant from their respective complementary films, and said films being positioned in a common focal plane, the transverse axis of which is parallel to a line drawn between the targets of said tubes, the distance of separation between said spaced apart tubes being to an extent that the image depth of the exposed films iterated and inconsistent with normal unmagnified stereoscopic observation, simultaneously exsin d films thr h the object by the tubes, processing a exposed films to develop them, and stcreoscopically observing the resultant images under conditions rnagnifi ion adapted to reconcile the exag gerated image depth with the image dimensions of width it c pile with the normal capacity for n stereoscopic vision.

5. The method of producing stereoscopically related films which comprises positioning two X-ray tubes apart from each other correlated with a given object, placing an Xray film in complementary relationship with each tube and adapted for respective exposure through the said object by the X-rays emanating from the tube with which it is complementary, said tubes being substantially equidistant from their respective complementary films, and said films being positioned in a common focal plane, the transverse axis of which is parallel to a line drawn between the targets of said tubes, the separation between said spaced apart tubes being to an extent that the paths of the X-rays adapted a on". the respective tubes intersect at the object a d at an angle of approximately 90, whereby the image depth of the exposed films will be substantially exaggerated and inconsistent with normal visual capacity for unmagnified stereoscopic observation, simultaneously exposing said films through the object by the respective tubes, processing the said exposed films to develop them, positioning the said processed films in a common focal plane for stereoscopic observation, the optical axis of the stereoscopic observation being substantially parallel to the transverse axis of the said common focal plane, and stereoscopically observing the resultant images under magnification to such an extent that the exaggerated image depth is reconciled with the image dimensions of width and height compatible with the normal capacity for stereoscopic vision.

6. The method of viewing stereoscopically related X-ray film images which comprises mounting the exposed stereoscopically coordinated films in a common focal plane, correlating the said films for movement as an integral assembly and relative to each other in the said plane, the latter movement comprising their separation and ap roximation as desi ed, whereby matched reas of the stereoscopically related films may be subject to viewing by the movement or" the films as an integral assembly into a zone of observation in the common focal plane, moving the resultant correlation of the films as an integral assembly into the viewing zone, laterally displacing the said films relati. an image conforntag with predetermined planar depth of the obiect observation at the said depth, and stereoscopically viewing the resultant image under conditions of magnification adapted to reconcile the exaggerated image dimensions for observation consonant with normal stereoscopic vision.

7. The method of stereoscopic observation which comprises preparing simultaneously exposed stereoscopically related affording an exaggerated image depth to an extent exceeding that compatible with normal unmagnified stereoscopic observation, processing the exposed films to develop them, mounting said developed correlated films in coordinated association with the viewing zone of a stereoscopic observing device and in a manner permitting the lateral and vertical movement ol' the correlated films as integral assembly into and through said viewing zone, moving matched areas of said correlated films into the zone stereoscopic observation by the said vertical and lateral movement of the integral assembly, adj' g the said matched areas to any predetermined depth of stereoscopic image object by the lateral and opposed movement or" the films relative to each other in said obsxving zone for effecting as desired their separation and approximation, and stereoscopically observing the image of said matched areas at the said predetermined depth under conditions of magnification adapted to reconcile the exaggerated image depth with the image dimensions of Width and height compatible with the normal capacity for stereoscopic vision.

8. The method of producing stereoscopically related films which comprises positioning X-ray tubes apart from each other and correlated with a given object, placing an X-ray film in complementary relationship with each tube and adapted for respective exposure through the said object by the X-rays emanating from the tube with which it is complementary, said tubes being substantially equidistant from their respective complementary films, said films being positioned in a common focal plane, the relative position of the said tubes and the said common focal plane bein such that a line drawn between the targets of said tubes is parallel to the transverse axis of said focal plane, simultaneously exposing said films through the object by the respective tubes with which they are complementary under conditions preventing interference, processing such exposed films, positioning said processed films in a common focal plane, said common focal plane being mounted in coordinated association with the viewing zone or" a stereo scopic observing device a manner permitting the lateral vertical movement of the processed films as an integral assembl into and away from said viewing zone, said mounting of the processed films permitting the horizontal movement or" he films relative to each other i in said common focal plane, and stereoscopically ob-' serving the resultant coordinated image under conditions such that the optical axis of stereoscopic observation is parallel to the transverse axis of the common focal' to each other for attaining 21 and approximation plane of said processed films, whereby when the unprocessed films and the processed films are respectively positioned so that they jointly lie in a common focal plane during the exposure stage and subsequently during the viewing stage, the said intertarget line and the said optical axis are both parallel to the transverse axis of the said common focal plane.

9. The method of producing stereoscopically related films which comprises positioning two X-ray tubes apart from each other and correlated with a given object, placing an X-ray film in complementary relationship with each tube and adapted for respective exposure through the said object by the X-rays emanating from the tube with which it is complementary, said tubes being substantially equidistant from their respective complementary films, and said films being positioned in a common focal plane of which the transverse axis is parallel to a line drawn between the targets of said tubes, the separation between said spaced apart tubes being to an extent that the paths of X-rays adapted to emanate from the respect-ive tubes intersect at the object and at an angle of approximately 90, whereby the image depth of the exposed films will be substantially exaggerated and inconsistent with normal visual capacity for stereoscopic observation, simultaneously exposing said films through the object by the respective tubes, processing said exposed films, mounting said exposed correlated films in a viewing zone and in a manner permitting the lateral and vertical movement of the correlated films as an integral assembly through said viewing zone and the horizontal movement of said films relative to each other in the said zone for effecting their separation and approximation, and observing the resultant images as to any unit matched area of the gross image, as well as at any applicable depth of said area within the object, by the lateral and vertical movement of said mounted films as an integral assembly into the viewing zone as well as by the movement of the films relative to each other in said zone, said observation being under conditions of magnification adapted to reconcile the exaggerated image depth with the image dimensions of width and height compatible with the normal capacity for stereoscopic vision.

10. The method as in claim 9 wherein the processed films are positioned in a common focal plane for stereoscopic observation and the optical axis of stereoscopic observation is substantially parallel to the transverse axis of the said common focal plane, whereby the films, in the unprocessed state and subsequently in the developed state, are positioned so that they comprise a common focal plane, the transverse axis of the said common focal plane bearing a parallel relationship to the said intertarget line and to the said optical axis respectively.

11. The method of producing stereoscopically related images which comprises positioning an X-ray film surface in complementary relationship with each of two respective sources of X-ray radiation, said film surfaces and radiation sources being correlated with a given object for the stereoscopic exposure of the films through said object,

the relative positions of said sources of radiation being .2:

separated to an extent such that the image depth of the exposed films will be exaggerated and inconsistent with normal visual capacity for stereoscopic observation, exposing the film surfaces through the said object by the said sources of radiation respectively coordinated therewith, processing said stereoscopically related exposed films, mounting said processed stereoscopically correlated films in a common focal plane and in coordinated association with the viewing zone of a magnifying stereoscopic observing device, said processed films being mounted in a manner permitting the lateral and vertical movement of the correlated films as an integral assembly into and away from said viewing zone, moving matched areas of saidcorrelated processed films into the zone of stereoscopic observation by the said vertical and lateral movement of the integral assembly, adjusting the said matched areas to any predetermined depth of stereoscopic image object by the movement of the films relative to each other in the said common focal plane, and stereoscopically observing the image of said matched areas at the said predetermined depth under conditions of magnification adapted to reconcile the exaggerated image depth with the image dimensions of width and height, corresponding with the normal visual capacity for stereoscopic observation.

12. The method of producing stereoscopically related images which comprises positioning an X-ray film surface in complementary relationship with each of two respective sources of X-ray radiation, said film surfaces and radiation sources being correlated with a given object for the stereoscopic exposure of the films through said object, the relative positions of said sources of radiation being separated to an extent affording predetermined image depth in said exposed films, exposing the film surfaces through the said object by the said sources of radiation respectively coordinated therewith, processing said stereoscopically related exposed films, mounting said processed stereoscopically correlated films in a common focal plane and in coordinated association with the viewing zone of a magnifying stereoscopic observing device, said processed films being mounted in a manner permitting the lateral and vertical movement of the correlated films as an integral assembly into and away from said viewing zone, moving matched areas of said correlated processed films into the zone of stereoscopic observation by the said vertical and lateral movement of the integral assembly, adjusting the said matched areas to any predetermined depth of stereoscopic image object by the movement of the films relative to each other in the said common focal plane, and stereoscopically observing the images of said matched areas at the said predetermined depth under conditions of magnification.

13. A stereoscopic X-ray apparatus comprising spaced apart X-ray tubes, a radiopaque tunnel associated with each said tube, each tunnel being coordinated at one of its ends with one of said tubes for controlling the direction of X-ray propagation from the said tube, a housing including an object zone, the said tunnels extending to the said object zone and merging with the said housing at said object zone, said housing having an end wall portion comprising a focal plane adapted for supporting X-ray films, each film being respectively complementary to one of said tubes for exposure thereby, and means in said housing adapted to substantially prevent interference in the exposure of the respective films by X-rays emanating through a tunnel from a tube not complementary thereto.

14. A stereoscopic X-ray apparatus combination comprising two X-ray tubes, two radiopaque tunnels, each tunnel associated at one of its ends with one of said tubes for controlling the direction of X-ray propagation from said tubes, an object zone, X-ray films supported adjacent said object zone for exposure in stereoscopically coordinated relationship with respect to the said object zone, each filrn being positioned in complementary relationship with one of said tubes and adapted for exposure by the X-rays emanating therefrom, said tubes being spaced apart and said tunnels merging, at their ends remote from the respective tubes, at the said object zone, the axes of the respective tunnels intersecting at the object zone at an angle of approximately whereby the image depth resulting from the exposure of the said films is exaggerated to an extent in excess of that acceptable to normal, unassisted visual stereoscopic capacity,

., means for substantially preventing interference in the exposure of the respective films by rays emanating from the tube not positioned in complementary relationship therewith, and means for simultaneously energizing said tubes to expose their respective complementary films.

15. A stereoscopic X-ray apparatus comprising two spaced apart X-ray tubes, two radiopaque tunnels, each tunnel associated at one of its ends with one of said tubes for controlling the direction of X-ray propagation from said tubes, a housing including an object zone, said tunnels converging toward said object zone and merging with said housing at said object zone, the longitudinal axes of said tunnels intersecting at approximately 90, said housing having an end wall portion comprising a frame structure adapted for supporting two X-ray films, each film being complementary to one of said tubes for exposure thereby, means in said housing defining said object zone for substantially preventing interference in the exposure of the respective films by rays emanating from the tube not complementary thereto, means in said object zone for supporting the object, gate means integral with said tunnels opening at the juncture of said tunnels adjacent said object zone Within the housing, and means for simultaneously energizing said tubes.

16. The combination as in claim 13, wherein a hypothetical line drawn between the tube targets is substantially parallel with the transverse axis of the focal plane common to the unprocessed films retained in position relative to the object for exposure.

17. An apparatus combination for viewing stereoscopically related X-ray film images of exaggerated dimensions comprising mounting means for supporting in a common focal plane the exposed and developed stereoscopically coordinated X-ray films providing said images, means for retaining said mounted X-ray films in an attached association relative to each other and permitting the lateral movement of the mounted films as an integral assembly into and from a zone of observation, and means for moving the said mounted X-ray films in an opposed horizontal direction relative to each other for effecting their separation and approximation, and thereby attaining an image conforming with any predetermined planar depth of the object in the zone of observation.

18. In a stereoscopic X-ray apparatus combination, means adapted for supporting for observation stereoscopically coordinated exposed films comprising frame members for separately retaining the exposed films in a given position, mounting means for seating said frame members in the same plane and adapted for permitting their lateral movement, means for attaching said frame members to each other whereby they are adapted for lateral movement as an integral assembly, means for horizontally separating and approximating said frame members relative to each other, a supporting structure for said mounting means permitting the vertical movement of said mounting means relative to said supporting structure, and means including viewing eye pieces for stereoscopically observing under conditions of magnification the aforesaid exposed films in their retained position, whereby stereoscopically related X-ray films retained in position by the said apparatus combination may be moved laterally and vertically as an integral assembly to bring any unit matched areas of the respective images into the zone of stereoscopic observation, and said films may be horizontally separated and approximated relative to each other to permit adjustment of the image depth of said matched image areas in the zone of observation. 19. The combination as in claim 18, wherein the stereoscopic viewing means includes the magnifying means as an integral part thereof and is adapted for movement in a horizontal plane perpendicular to the plane of the film retaining means and to the said means for mounting the latter and said stereoscopic viewing means is attached to the supporting structure for the mounting means of the film frames.

20. In a stereoscopic X-ray apparatus combination, means adapted for supporting for observation stereoscopically coordinated exposed films comprising frame members for separately retaining the exposed films in a given position, mounting means for seating said frame members in the same plane and adapted for permitting their lateral movement, means for attaching said frame members to each other whereby they are adapted for lateral movement as an integral assembly and for their horizontal separation and approximation relative to each other, a supporting structure for said mounting means permitting the vertical movement of said mounting means relative to said supporting structure, whereby stereoscopically related films retained in position by the said apparatus combination may be moved laterally and vertically as an integral assembly, and said films may be horizontally separated and approximated relative to each other.

21. The combination as in claim 18, wherein a horizontal line perpendicular to the optical axis of the viewing eye pieces and extending to the zone of observation in the focal plane, in which the retained processed films are positioned for movement, is substantially perpendicular to the said zone of observation.

22. The combination as in claim 17, wherein the means for retaining said mounted X-ray films in an attached association permitting the lateral movement as an integral assembly, and the means for moving the said mounted X-ray films relative to each other comprise a reversely threaded screw member adapted for retaining the said mounted X-ray films in an attached association and for the synchronized opposed lateral displacement of the mounting means relative to each other.

23. The combination as in claim 20, wherein the means for attaching the frame members to each other comprises a reversely threaded screw member adapted for the synchronized opposed lateral displacement of the said frame members relative to each other, whereby the said frame members are capable of lateral movement as an integral assembly and of opposed lateral movement relative to each other.

References Cited in the file of this patent UNITED STATES PATENTS 733,756 Snook July 14, 1903 1,904,868 Kurtz Apr. 18, 1933 2,088,041 Smith July 27, 1937 2,339,822 Blaricon et al Jan. 25, 1944 2,391,675 Brown Dec. 25, 1945 2,559,698 Bahre July 10, 1951 FOREIGN PATENTS 308,050 Italy May 22, 1933 487,389 Great Britain Aug. 26, 1936 

